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  NOTE: This part requires additional parts in order to function properly. Please add all additional required parts to your order as needed.  These link will take you to the needed parts:


  • Iridium IX Spark Plug
  • Connecting Air Tube
  • High-Flow Oil Pump
  • Intake Manifold
  • Hurricane Racing Air Filter
  • Intake Manifold
  • Fuel Injector Adapter Kit
  • Throttle Body
  • High Flow Fuel Injector


Ideal engine part to complete Koso's big bore kit

Unique four-valve design increases air flow and performance

Provides more power and torque

Features a forged piston, stainless steel 24 mm intake valves and 20 mm exhaust valves

2014 - 20 Honda Grom / Monkey Koso 4 Valve Head Kit 170CC Big Bore Kit

SKU: MB-0950-0754
$1,039.95 Regular Price
$899.99Sale Price
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